{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T16:07:51Z","timestamp":1783440471750,"version":"3.54.6"},"reference-count":33,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,1,9]],"date-time":"2025-01-09T00:00:00Z","timestamp":1736380800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Muscles"],"abstract":"<jats:p>Friedreich\u2019s ataxia (FRDA) results from a faulty mitochondrial protein known as Frataxin. The purpose of this case report was to test whether skeletal muscle in FRDA can adapt to an endurance-based training program using neuromuscular electrical stimulation (NMES). A 36-year-old female with FRDA completed twelve training sessions, each lasting 30 min over 30 days, focused on the forearm muscles using NMES. Pre- and post-training session measurements of contractions, muscle-specific endurance, and muscle mitochondrial capacity were taken per training session. Training contractions increased from 4200 to 9420. Muscle-specific endurance increased by 14% at 2 Hz and 17% at 4 Hz. Muscle endurance at 6 Hz increased from 0% to 51%. The rate constant of mitochondrial capacity was 0.95 min\u22121 pre- and 0.99 min\u22121 post-training session. In conclusion, one month of NMES increased training volume and muscle-specific endurance but did not change mitochondrial capacity. Muscle adaptations to endurance training were seen in FRDA, but increased training might be needed to test if mitochondrial capacity can improve.<\/jats:p>","DOI":"10.3390\/muscles4010001","type":"journal-article","created":{"date-parts":[[2025,1,9]],"date-time":"2025-01-09T05:17:08Z","timestamp":1736399828000},"page":"1","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Muscle Endurance Training in a Person with Friedreich\u2019s Ataxia"],"prefix":"10.3390","volume":"4","author":[{"given":"Nicole T.","family":"McGarrell","sequence":"first","affiliation":[{"name":"Department of Kinesiology, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Max E.","family":"Green","sequence":"additional","affiliation":[{"name":"Northside Hospital, Atlanta, GA 30342, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9850-487X","authenticated-orcid":false,"given":"Kevin K.","family":"McCully","sequence":"additional","affiliation":[{"name":"Department of Kinesiology, University of Georgia, Athens, GA 30602, USA"},{"name":"InfraredRx, Inc., Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1423","DOI":"10.1126\/science.271.5254.1423","article-title":"Friedreich\u2019s Ataxia: Autosomal Recessive Disease Caused by an Intronic Gaa Triplet Repeat Expansion","volume":"271","author":"Campuzano","year":"1996","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1346","DOI":"10.1016\/S1474-4422(16)30287-3","article-title":"Progression Characteristics of the European Friedreich\u2019s Ataxia Consortium for Translational Studies (Efacts): A 2 Year Cohort Study","volume":"15","author":"Reetz","year":"2016","journal-title":"Lancet Neurol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"572","DOI":"10.1002\/acn3.315","article-title":"Cognition in Friedreich\u2019s Ataxia: A Behavioral and Multimodal Imaging Study","volume":"3","author":"Dogan","year":"2016","journal-title":"Ann. 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